Facebook’s 11-month-old Messenger mobile app for sending texts and exchanging photos and locations with friends, is putting on its big boy pants today, maturing into a full-featured chat and messaging service with bigger photos, better notifications, and all-around improved performance.

Messenger, updated for iPhone and Android Monday, comes with enhanced push notifications and new in-app notifications, which are designed to make it easier for the Facebook chatty Cathy to switch between multiple conversations faster.

Version 1.8 allows users to share larger photos so that recipients can view full-screen photos and pinch to zoom in. The tweaked app also introduces the ability for group chatters to include friends of friends in threads. It also adds little goodies such as the ability to swipe (iPhone) or tap (Android) to delete individual messages from conversations.

The app should be noticeably speedier, as Facebook has made Messenger faster to load, swifter to navigate, and hastier when it comes to sending and receiving messages.

Combine today’s updates with earlier improvements that introduced read receipts, and location and real-time typing indicators, and what you get is a far more complete messaging app that can better go head-to-head with app makers, carriers, and Apple in the messaging area.

Facebook, then, is sending us the message that it’s not only committed to perfecting its cross-platform messaging app, but that it wants Messenger to become your default app for mobile communication.

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